At present, a liquid crystal display (LCD) generally uses a white light emitting diode (LED) as a backlight which coordinates with a RGB (Red, Green, and Blue) color filter to realize a pixel coloring function, and the color filter work to filter corresponding color lights in the white light. However, this approach has the following defects:
(1) Because R, G, and B color blocks only respectively allow light corresponding to red, green and blue spectra in white light to pass through, there is loss of the light to a certain degree when it transmits. In order to facilitate understanding, please refer to FIG. 1 (FIG. 1 is a schematic diagram of principle of optical loss). As illustrated in FIG. 1, since there is a refractive index difference between photo resist and glass, when light transmits through an interface between the two, partial light will be reflected to form reflected light 1, and there will be a second time of light reflection on the boundary between the glass and air to form reflected light 2. The reflected light 1 and the reflected light 2 are the main cause for optical loss, while reflected light formed through other light reflection (for example, reflected light 3) may be ignored. It is seen that the light loss shown by FIG. 1 will surely decrease a light transmission rate of an incident light.
(2) When light transmits a color filter (CF), selectivity is comparatively low, which will decrease color gamut of the light.